Ike Skelton, a Missouri Democrat who spent more than three decades in Congress and served as chairman of the House Armed Services Committee, died today. He was 81.
Two senior House aides confirmed Skelton's death to ABC News.
Skelton, who was elected to 17 terms in the House, fell short in his bid for re-election in 2010 when Democrats lost control of the House. His defeat became a symbol of the tea party wave that swept Republicans into power.
Vicky Hartzler, a Republican, won the race and re-election in 2012.
Skelton was a champion of the military - and military spending - and vigorously defended Fort Leonard Wood and Whiteman Air Force Base in his sprawling rural Missouri district.
Vice President Joe Biden mourned Skelton this evening, describing him s a "classy guy."
"He was a great friend," Biden said at the Capitol after dinner with House Democrats. "He campaigned for me way back early on. I was in and out of his district a lot. He helped me when I was trying to get the nomination. He helped me win re-election.
"You know, he had that ingredient that a lot of Democrats and Republicans have that is the ultimate currency in this place. He had absolute, total, thorough integrity. Whatever he told you he would do - no exaggeration - you could count on it. Too many people today say, 'Well, I'm with you' but then they come back and say, 'Well, my circumstances changed.' Even if his circumstances changed, he'd stay with you if he told you."
House Democratic Leader Nancy Pelosi praised Skelton for his 34 years of service in Congress.
"He fought to bridge what he called 'a chasm between those who protect our freedoms and those who are being protected,'" Pelosi said in a statement. "From their quality of life to their readiness for war, he made sure that every man and woman in uniform who put their lives on the line would receive the support they had earned and the deepest respect they deserved."
Sen. Roy Blunt, a Missouri Republican who served alongside Skelton, echoed the praise.
"No member of the Congress was more dedicated to America's defense and those who defend us than Ike Skelton," Blunt said in a statement. "He loved our country and its history and will be remembered for his contributions to both."
Skelton died today at Virginia Hospital Center in Arlington, Va., the Democratic officials said, where he was surrounded by family and friends.
ABC News' Devin Dwyer contributed to this story.